Down the Drain: Regulatory Status
Despite mounting evidence concerning the potential health effects of exposures to chemicals that disrupt the hormone system, much remains to be done to protect people and the environment from this broad spectrum of chemicals. The Toxic Substances Control Act, the law that regulates chemicals in the United States, was created before the science behind hormone-disrupting agents began to develop. As a result, the current system of chemical regulation in the U.S. is not designed to identify and act against chemicals of concern that can harm the hormone systems of people, fish, and wildlife. New legislation is an essential tool to safeguard Americans and our environment from hormone-disrupting chemicals.
A patchwork of current federal initiatives attempts to reduce exposures to phthalates, bisphenol A, and triclosan. For example, phthalates are considered a hazardous waste and are regulated as pollutants when released into the environment (e.g. EPA 2006). One phthalate, DEHP, is regulated in drinking water. In addition, this phthalate was removed voluntarily from children's toys more than a decade ago. (Despite this, 2 recent studies (Purvis 2005; Kay 2006) have detected DEHP and other phthalates subject to this voluntary action in toys on the market today.) Yet most phthalates are unregulated in food, cosmetics, and consumer and medical products, and through their use, may enter the environment where they can harm people, fish, and wildlife. Phthalates have been shown to bioaccumulate in fish tissue and to affect estrogen levels in fish (Jobling 1995).
Examination of infants receiving intensive care revealed exposures to DEHP via medical devices at levels comparable to those causing health effects in laboratory animals (Calafat 2004). Studies of pollution in people performed by the Centers for Disease Control and Prevention (CDC) indicate many women are exposed to DEHP and other phthalates at levels above the government's safe dose designed to protect against birth defects (Kohn 2000). Despite these findings, efforts to reduce exposures of Americans to phthalates have faltered at the federal level.
Government reviews of the toxicity of bisphenol A rarely consider recent studies suggesting this chemical can produce adverse health effects at low doses. The U.S. Environmental Protection Agency (EPA) established its safety standard for bisphenol A (the reference dose, or RfD) in 1987, a decade before the BPA low-dose literature was established (EPA 1987). The vast majority of studies finding bisphenol A toxic at low doses have been published since 1997, the year that a pivotal animal study showed BPA's ability to harm the prostate at levels far below what was thought safe (Nagel 1997). EPA's safety standard is 25 times greater than a dose now known to cause birth defects in animal studies (50 ug/kg/d vs. 2 ug/kg/d), and has not been updated for 20 years.
Ten years ago, the U.S. Food and Drug Administration (FDA) published estimates of infant and adult bisphenol A exposures (FDA 1996). Despite the fact that FDA has not yet established an Acceptable Daily Intake (ADI) for BPA, and has not conducted its standard toxicology study to determine a safe dose for humans (FDA 2007), in 2005 an FDA official asserted that "...FDA sees no reason to change [its] long-held position that current [BPA] uses with food are safe" (FDA 2005). A 2001 assessment of BPA by the U.S. National Toxicology Program, which found BPA safe at low doses, occurred before the publication of dozens of BPA studies that substantially bolster the evidence for low-dose effects (NTP 2001; vom Saal 2005).
The Center for the Evaluation of Risks to Human Reproduction (CERHR), an agency within the National Institutes of Health, began a review of the health risks associated with bisphenol A earlier this year. However, an Environmental Working Group investigation revealed that CERHR was run by a consulting group, Sciences International, with ties to companies that manufacture BPA (EWG 2007b). In preparation for the CERHR evaluation, Sciences International staff prepared a report that reviewed the scientific literature surrounding bisphenol A. This report omitted at least 12 studies showing low-dose toxicity. Following EWG allegations of conflict of interest, CERHR delayed its evaluation of bisphenol A, and terminated its 5 year, 5 million dollar contract with Sciences International in its fourth year.
Triclosan has received little attention to date from U.S. agencies charged with public health protection. An FDA panel evaluated research on household use of antibacterial products, such as those containing triclosan, at the urging of the American Medical Association. The FDA found no evidence that those using antibacterial products in their homes were healthier than those using soap and water and other typical cleansing products lacking specific antibacterial agents (FDA 2005). The American Medical Association is concerned that increased use of antibacterial products in the home will lead to the development of microbial resistance to antibiotic agents (Tan 2002).
Although a triclosan byproduct has been detected in San Francisco Bay (Oros 2002) and numerous studies have shown effects to aquatic life at the concentrations found in the environment (e.g. Samsoe-Petersen 2003; Orvos 2002; Ishibashi 2004), no regulatory controls on the sale and use of triclosan have been developed.
Local efforts to reduce use of these hormone-disrupting chemicals have met with mixed success. The City of San Francisco's Stop Toxic Toys bill requires testing of up to 100 children's products each year, and prohibits the sale of those products that contain high levels of phthalates. The original bill, passed in 2006, also targeted products containing bisphenol A; however, lawsuits on behalf of chemical manufacturers pushed city supervisors to adopt a less protective law. San Francisco supervisors will reconsider a bisphenol A ban if the California State Legislature has not done so in the next year.
Meanwhile, nearby cities of Palo Alto and San Jose have phased out municipal purchases of products containing triclosan. The East Bay Municipal Utility District (EBMUD), EWG's technical partner in the present study of sources of hormone-disrupting chemicals in San Francisco Bay, is phasing out purchases of triclosan, as well as its chemical cousin, triclocarban. Similar local efforts to reduce exposures to phthalates, bisphenol A, and triclosan are underway in a few other parts of the country as well.
Federal regulation is essential to protect all Americans from the harmful effects of exposures to hormone-disrupting chemicals. Phthalates, bisphenol A, and triclosan are just a few of hundreds of chemicals that may harm people, fish, and wildlife - highlighting the need to begin reform of our system of chemical regulations. The nation's system of regulations for industrial chemicals like these are embodied in the Toxic Substances Control Act, a law passed in 1976, and the only major environmental or public health statute that has never been updated. Under this law, companies are not required to test chemicals for safety before they are sold, and are not required to track whether their products end up in people or the environment at unsafe levels. As a result, phthalates, bisphenol A, and triclosan are widely used, are allowed in unlimited quantities in a broad range of consumer products, are found in people, fish, and wildlife, and often lack safety standards.